DNA and host cells encoding a cell surface protein of porphyromonas gingivalis

ABSTRACT

A DNA encoding a cell surface polypeptide of Porphyromonas gingivalis, and a recombinant DNA being a DNA having integrated the encoding DNA thereinto. The cell surface polypeptide of the periodontopathic organism useful for prophylaxis and diagnosis of periodontal diseases can be obtained in a large amount by a microorganism containing the recombinant DNA wherein the DNA was integrated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a cell surface polypeptide of Porphyromonas (Bacteroides) gingivalis (another name; periodontopathic organism: hereinafter, referred to as Porphyromonas gingivalis) having a molecular weight of about 72-kDa (kilodalton) (hereinafter abbreviated as periodontopathic organism cell surface polypeptide), a DNA encoding the polypeptide, a recombinant DNA wherein the DNA is integrated and a microorganism containing the recombinant DNA.

The DNA obtained in the invention can be utilized as a reagent, namely as a probe for detecting Porphyromonas gingivalis. Further, the periodontopathic organism cell surface polypeptide obtained in the invention and produced by a microorganism can be utilized for a diagnosis of patients suffering with periodontal diseases and having antibodies against Porphyromonas gingivalis, as an antigen for preparing an antibody for diagnosing patients suffering with periodontal diseases and having Porphyromonas gingivalis or as a prophylactic vaccine for periodontal diseases.

2. Description of Related Art

It is reported by Yoshimura et al. in Infect. Immun., 57, 3646 (1989) that since the periodontopathic organism cell surface polypeptide exhibits strong immune response to the sera of patients of periodontal diseases, infecting with Porphyromonas gingivalis, antibodies against the polypeptide existing in the sera of the patients can be detected using it. Further, it is reported by Ogawa et al. in Nippon Saikin-gaku Zasshi, 44, 329 (1989), by Yoshimura et al. in J. Bacteriol., 160, 949 (1984) and by Yamaji et al. in Nisshishushi, 33, 349 (1991) that the immune response of the polypeptide is different from that of the known fimbrial protein from the known periodontopathic organism having a molecular weight of 41 kDa, and thus the periodontopathic organism cell surface polypeptide of the invention is different from the ciliary protein.

As to the structure of the periodontopathic organism cell surface polypeptide, its amino acid composition is reported by Yoshimura et al. in Infect. Immun. 57, 3646 (1989), and the amino-terminal amino acid sequence of a purified polypeptide thereof is reported by Yoshimura et al. in FEMS Microbiol. Lett., 92, 47 (1992). Elucidated amino acids are 40 amino acids, and when we compare 40 amino acid with an amino acid number estimated from the molecular weight of the periodontopathic organism cell surface polypeptide, the rate is only under 10%. Further, concerning with a DNA encoding the periodontopathic organism cell surface polypeptide, it is reported by Yoshimura et al. in FEMS Microbiol. Lett., 92, 47 (1992) that its part was obtained. However the base sequence of the gene is not elucidated at all.

The periodontopathic organism cell surface polypeptide is recovered from Porphyromonas gingivalis cells, but its supply amount is limited because of difficulty of the culture of Porphyromonas gingivalis. Thus development of an industrial process for supplying the periodontopathic organism cell surface polypeptide is desired.

SUMMARY OF THE INVENTION

According to the invention, there are provided a cell surface polypeptide of Porphyromonas gingivalis having an amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558), a DNA encoding the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558), a recombinant DNA which is a DNA having integrated thereinto the DNA encoding the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558), and a microorganism having the recombinant DNA which is the DNA having integrated thereinto the DNA encoding the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID No. 1 (Numbers 1-558).

Further, the DNAs encoding the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558) according to the present invention include those wherein one or plural bases are added, deleted or replaced by site-directed mutagenesis (Nucleic Acid Research, 10, 6487-6508 (1982)). Therefore, a recombinant DNA wherein a DNA obtained by the mutagenesis is integrated, and a microorganism having the recombinant DNA are also included in the invention. Since a polypeptide produced by recombinant technique using a DNA wherein in the DNA encoding the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558), one or plural bases are added, deleted or replaced, is a polypeptide wherein in the cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 (Numbers 1-558), one or plural amino acids are added, deleted or replaced, this polypeptide is also included in the invention.

A DNA sequence encoding the amino acid sequence shown in SEQ ID No: 1 is shown in SEQ ID No: 3, wherein bases 76-1749 encodes amino acids 1-558.

BRIEF DESCRIPTION OF DRAWING

FIG. 1 is a drawing illustrating the process of creating a recombinant plasmid containing a DNA encoding the periodontopathic organism cell surface polypeptide.

DETAILED DESCRIPTION OF THE INVENTION

The DNA and recombinant DNA of the invention are prepared according to the following general process.

The whole DNA is prepared from Porphyromonas gingivalis according to the method of Meyer et al. (Cell, 30, 45 (1982)) and the method of Maniatis et al. (Molecular Cloning Laboratory Manual 2nd ed., Cold Spring Harbor Laboratory Press, published in 1989 (hereinafter referred to as Mol. clon.)), and the DNA is inserted into a vector DNA such as a plasmid DNA of Escherichia coli to give a library of recombinant DNAs. From the recombinant DNA library, a recombinant DNA having a DNA encoding the periodontopathic organism cell surface polypeptide is selected.

The culture broth of Porphyromonas gingivalis is centrifuged, the cells are collected, lysozyme, proteinase K and sodium dodecyl sulfate (SDS) are added thereto, and the cells are ruptured and dissolved. After phenol extraction, phenol-chloroform extraction and chloroform extraction, DNAs are recovered by ethanol precipitation.

The extracted DNAs are treated with 5 to 100 units/ml, preferably 10 units/ml of a restriction enzyme KpnI in a suitable solution, e.g. a solution containing 10 mM Tris-HCl buffer (e.g. pH 7.5), MgCl₂ (e.g. 6 mM) and NaCl (e.g. 10 mM), and then NaCl is added so as to be 100 mM and the DNA is treated with 5 to 100 units/ml, preferably 10 units/ml of a restriction enzyme XhoI. The DNAs after the treatment are fractionated using low melting point agarose gel electrophoresis (Lars Wieslander: Anal. Biochem., 98, 305 (1979)), and fragments of about 3.4 kilobases are recovered and integrated into a vector.

As the vector Blue-script, pUC18, pUC19, etc. can for example be used. When Blue-script is used, the vector DNA is treated with 5 to 100 units/ml, preferably 10 units/ml of a restriction enzyme KpnI in a suitable solution, e.g. a solution containing 10 mM Tris-HCl buffer (e.g. pH 7.5), MgCl₂ (e.g. 6 mM) and NaCl (e.g. 10 mM), and then NaCl is added so as to be 100 mM and the DNA is treated with 5 to 100 units/ml, preferably 10 units/ml of a restriction enzyme XhoI to cleave the KpnI and XhoI sites of the vector DNA. These DNAs are fractionated using low melting point agarose gel electrophoresis (Lars Wieslander: Anal. Biochem., 98, 305 (1979)), and a fragment of about 2.9 kilobases is recovered.

This vector DNA fragment and the previously prepared DNA fragments are incubated for a definite time (e.g. 2 hours) at an appropriate temperature (e.g. 16° C.) using a DNA ligation kit (produced by Takara Shuzo Co.). Thus recombinant DNAs are obtained.

Using the obtained recombinant DNA, Escherichia coli, for example an XL1-Blue strain, an LE 392 strain, DH 5 strain or a JM 83 strain is transformed, for example according to the method of Scott et al. (Katsuya Shigesada: Saibo Kogaku, 2, 616 (1983)). When Blue-script is used as the vector, since the ampicillin-resistant gene exists on the recombinant DNAs, the transformed Escherichia coli strains exhibit ampicillin resistance. Hereinafter, a method for selecting a strain having a novel recombinant DNA carrying the periodontopathic organism cell surface polypeptide gene from the ampicillin-resistant (Ap^(r)) transformants is described. Namely, the obtained recombinant DNAs are fixated on a nitrocellulose filter, and associated with a synthetic DNA probe having a DNA sequence estimated from the amino acid sequence of the periodontopathic organism cell surface polypeptide, and ones strongly associating therewith are selected (the method of Grunstein-Hogness, Proc. Natl. Acad. Sci. U.S.A., 72, 3961 (1975)). The probe DNA is synthesized by a usual triester method (J. Am. Chem. Soc., 97, 7327 (1975)). The selection with the synthetic DNA probe can further be ascertained according to the method of Southern et al. (J. Mol. Biol., 98, 503 (1975)), and by this method a recombinant DNA having the DNA fragment encoding periodontopathic organism cell surface polypeptide can be identified.

An example of the thus obtained recombinant DNAs is a plasmid pCSP 409. This plasmid can be used as a supply source of the DNA encoding the periodontopathic organism cell surface polypeptide.

Further, a DNA encoding the periodontopathic organism cell surface polypeptide is cut out from the novel recombinant DNA of the invention, the DNA is integrated into an expression vector DNA, the resultant recombinant DNA is introduced into a microorganism, the resultant transformed microorganism is cultured to form and accumulate the periodontopathic organism cell surface polypeptide in the culture broth, and the polypeptide is recovered. Thereby the polypeptide can be prepared.

As the recombinant DNA containing the DNA encoding the periodontopathic organism cell surface polypeptide, the above plasmid pCSP 409 can be mentioned as a suitable example. As the expressing vector DNA, any one can be used so long as it can express the inserted DNA in the microorganism. Preferably, there can be used a vector DNA which has a suitable promoter, e.g. the promoter of the tryptophan (trp) system, the lactose (lac) system, the PL system or the like, into the downstream of which a DNA can be inserted, and further wherein the interval between the contained Shine-Dalgarno sequence (hereinafter abbreviated as SD sequence) and the translation initiation codon (ATG) is adjusted to a suitable distance, e.g. 6 to 18 base pairs. As a specifically preferred vector DNA, plasmid pGEL1 can be mentioned. An Escherichia coli containing pGEL1 is deposited with National Institute of Bioscience and Human Technology, Agency of Industrial Science and Technology (Bikoken) on Oct. 6, 1984 as Escherichia coli IGEL1 (FERM BP-629).

Recombination between the DNA encoding the polypeptide and the vector DNA can be conducted by a method described in Mol. clon., namely using a general recombinant DNA method to digest both DNAs with a restriction enzyme and conduct ligation with T4DNA ligase. Purification of DNA fragments formed by the restriction enzyme digestion is conducted by low melting point agarose gel electrophoresis (L. Wieslander: Anal. Biochem., 98, 305 (1979), hereinafter referred to as LGT method), etc. The ligation reaction of the DNA fragments is conducted at 5 to 25° C., preferably 16° C. for 15 minutes to 16 hours, using a DNA ligation kit (produced by Takara Shuzo Co.), or at 1 to 37° C. (preferably 3 to 20° C.) for 15 minutes to 72 hours (preferably 2 to 20 hours) in a reaction solution containing 2 to 200 mM (preferably 10 to 40 mM) of Tris-HCl (pH 6.1 to 9.5, preferably pH 7.0 to 8.0), 2 to 20 mM (preferably 5 to 10 mM) of MgCl₂, 0.1 to 10 mM (preferably 0.5 to 2.0 mM) of ATP and 1 to 50 mM (preferably 5 to 10 mM) of dithiothreitol, using 0.3 to 10 units of T4DNA ligase.

The resultant recombinant DNA is introduced into a microorganism, if necessary using the transformation method of Cohen et al. (S. N. Cohen et al.: Proc. Natl. Acad. Sci. U.S.A., 69, 2110 (1972)). As the microorganism, any one can be used so long as it can express the DNA encoding the periodontopathic organism cell surface polypeptide of the invention, and form and accumulate the polypeptide in the culture broth. Preferably used is Escherichia coli.

Isolation of the DNA encoding the periodontopathic organism cell surface polypeptide from the Escherichia coli having the recombinant DNA for determining the base sequence of the DNA is conducted using the method of Birnboim et al. (H. C. Birnboim et al.: Nucleic Acids Res., 7, 1513 (1979)), etc.

The isolated recombinant DNA is digested with 1 to 10 kinds of restriction enzymes and then treated by agarose gel electrophoresis or polyacrylamide gel electrophoresis, and the cleavage sites are checked. The base sequence of the DNAs is determined according to Maxam-Gilbert method (Proc. Natl. Acad. Sci., 74, 560 (1977)) or Sanger method using M13 phage (Sanger et al., Proc. Natl. Acad. Sci. U.S.A., 74, 5463 (1977); Amersham Co., M13 Cloning and Sequencing Handbook).

Preparation of the periodontopathic organism cell surface polypeptide from the microorganism having the recombinant DNA wherein the DNA encoding the cell surface polypeptide of Porphyromonas gingivalis is integrated can be conducted by culturing the microorganism in a medium, and recovering and purifying the polypeptide accumulated in the culture broth or in the cells.

As the medium, any one can be used so long as it is suitable for the groth of the microorganism and the production of the periodontopathic organism cell surface polypeptide, and synthetic media, natural media, etc. are used.

There can be used as carbon sources glucose, fructose, lactose, glycerol, mannitol, sorbitol, etc., as nitrogen sources ammonium chloride, ammonium sulfate, Casamino acid, yeast extract, polypeptone, meat extract, Bacto-tryptone, etc., as other nutrients potassium dihydrogenphosphate, dipotassium hydrogenphosphate, sodium chloride, magnesium sulfate, vitamin B₁, magnesium chloride, etc.

Culture is conducted at a pH of 5.5 to 8.5 and a temperature of 18 to 40° C. preferably by stirring culture. After the start of the culture, the periodontopathic organism cell surface polypeptide is accumulated in 5 to 90 hours. When a microorganism such as Escherichia coli accumulating the polypeptide intracellularly is used, the cells are collected from the culture broth by centrifugation, etc. and ruptured by ultrasonic treatment, etc. to give an extract. When a microorganism secreting the periodontopathic organism cell surface polypeptide extracellularly is used, the culture broth is used as an extract.

Purification of the periodontopathic organism cell surface polypeptide from the extract can be conducted according to fractionation with a base or solvent, ion exchange chromatography, gel filtration, affinity chromatography, etc.

Detection of the resultant periodontopathic organism cell surface polypeptide can be conducted according to immunoassay, particularly using Western blot technique (Proc. Natl. Acad. Sci. U.S.A., 76, 4350 (1979)), etc.

Examples of the invention are set forth below.

EXAMPLE 1

(1) Preparation of the Genomic DNA from Porphyromonas gingivalis

The genomic DNA was prepared as follows from Porphyromonas gingivalis according to the method of Meyer et al. (Cell, 30, 45 (1982)). The cells of Porphyromonas gingivalis (5 g) (wet weight) was suspended in 10 ml of 50 mM Tris-HCl (pH 7.5) containing 50 mM EDTA and 50 mM NaCl, 2 mg/ml of lysozyme was added, incubation was conducted at 37° C. for 10 minutes, 0.5 mg/ml of proteinase K and 1.5% of SDS were added, and incubation was conducted at 50° C. for 6 hours to solubilize the cells. An equal amount of a phenol solution was added to this homogenate and extraction was conducted three times, and then extraction was conducted twice with phenol-chloroform and further once with chloroform. After the extraction, DNA was recovered by ethanol precipitation. The DNA precipitate was dissolved in 2 ml of a Tris-HCl (pH 8.0) solution containing 1 mM EDTA, 2 μg/ml of RNase was added, and incubation was conducted at 65° C. for 4 hours. Then, 200 μl of 3M sodium acetate solution and further equal amount of isopropyl alcohol were added and the deposited DNA was recovered by centrifugation. The resultant DNA (about 10 mg) was dissolved in 1 ml of a solution consisting of 10 mM Tris-HCl (pH 8.0) and 1 mM EDTA.

(2) Insertion of the plasmid of Porphyromonas gingivalis into a Vector

Creation of a recombinant DNA was conducted according to Mol. clon. The outline of the steps was shown in FIG. 1. The above genomic DNA of Porphyromonas gingivalis (300 μg) was added to 300 μl of a solution consisting of 10 mM Tris-HCl (pH 7.5), 6 mM MgCl₂ and 10 mM NaCl, 500 units of KpnI (produced by Takara Shuzo Co., hereinafter all restriction enzymes are produced by Takara Shuzo Co. unless otherwise noted) was added, and reaction was conducted at 37° C. for 6 hours. Then, NaCl was added so as to be 100 mM, 500 units of XhoI was added and reaction was conducted at 37° C. for 3 hours. About 50 μg of fragments each of about 3.4 kb were obtained from this reaction solution according to LGT method. Further, 10 μg of a vector plasmid (Bluescript) DNA was added to 30 μl of a solution consisting of 10 mM Tris-HCl (pH 7.5), 6 mM MgCl₂ and 10 mM NaCl, 50 units of KpnI was added, and reaction was conducted at 37° C. for 6 hours. Then, NaCl was added so as to be 100 mM, 50 units of XhoI was added and reaction was conducted at 37° C. for 3 hours. About 5 μg of a fragment of about 2.9 kb was obtained from this reaction solution according to LGT method. This fragment was mixed with 30 μg of the genomic DNA of Porphyromonas gingivalis treated with the restriction enzymes and incubation was conducted at 16° C. for 2 hours using a DNA ligation kit (produced by Takara Shuzo Co.) to give recombinant DNAs containing the genomic DNAs of Porphyromonas gingivalis.

(3) Selection of Recombinant DNAs containing the DNA Encoding the Periodontopathic Organism Cell Surface Polypeptide

An Escherichia coli strain XL1-Blue (STRATAGENE Co.) was transformed according to the method of Scott et al. (Katsuya Shigesada: Saibo Kogaku, 2, 616 (1983)) using the recombinant DNA obtained in Example 2. The resultant about 10,000 colonies were fixated on nitrocellulose. A synthetic DNA represented by the following formula (SEQ ID NO: 2) corresponding to the sequence of 7 amino acids at the N-terminal site of the purified cell surface polypeptide

    Formula CARGAYCARG CNAAYCCNGA 20

(wherein the base symbols are based on the guideline for preparation of a specification containing base sequences or amino acid sequences) was labeled with digoxigenin (hereinafter referred to as DIG) at the 3'-terminus, using DIG Oligonucleotide 3'-End Labeling Kit, BOEHRINGER MANNHEIM GmbH according to the operation method in the attached manual. Thus, 3 strains wherein strong association with the DIG-labeled probe was observed at 40° C. were selected (the method of Grunstein-Hogness, Proc. Natl. Acad. Sci. U.S.A., 72, 3961 (1975)). On the obtained 3 strains, association with the above probe was ascertained according to the method of Southern (J. Mol. Biol., 98, 503 (1975)). These plasmids were designated pCSP409-A, B and C, and all of them were thought to contain a DNA encoding the periodontopathic organism cell surface polypeptide because they have the DNA sequence expected from the amino acid sequence of the purified periodontopathic organism cell surface polypeptide.

The above pCSP409-A is hereinafter called pCSP409, and the whole nucleotide sequence of its translation region was determined according to Sanger method using M13 phage (Sanger et al., Proc. Natl. Acad. Sci. U.S.A., 74, 5463 (1977): Amersham Co. M13 Cloning and Sequence Handbook)). Thus revealed base sequence and the amino acid sequence determined therefrom are shown in SEQ ID NO: 1.

The Escherichia coli containing the recombinant plasmid wherein pCSP409 was integrated was deposited with the National Institute of Bioscience and Human Technology, Agency of Industrial Science and Technology, 1-3, Higashi 1-chome, Tsukuba-shi, Ibarakiken, 305 Japan, Bikoken on Mar. 23, 1994 as Escherichia coli CSP409 (accession number FERM BP-4614).

(4) Production of the Periodontopathic Organism Cell Surface Polypeptide from Escherichia coli CSP409

Escherichia coli CSP409 obtained in (3) was inoculated in 10 ml of MCG medium (containing 0.6% disodium hydrogenphosphate, 0.3% potassium dihydrogenphosphate, 0.5% sodium chloride, 0.1% ammonium chloride, 0.5% glucose, 0.5% Casamino acid, 1 mM magnesium sulfate and 4 μg/ml vitamin B₁, pH 7.2), and cultured at 30° C. for 7 hours. The resultant culture broth was inoculated in 50 ml of MCG medium and cultured at 30° C. for 5 hours.

The cells were recovered from the culture broth by centrifugation (CR-20 produced by Hitachi, Ltd., Rotor RPR16-516; 8,000 rpm, 10 minutes). The resultant cells was dissolved in the buffer of Remuli (pH 7.4; Nature, 227, 680 (1970)), and assay was conducted according to Western blot technique (Proc. Natl. Acad. Sci. U.S.A., 76, 4350 (1979)) using the serum of a patient suffering with a periodontal disease and the serum of a normal subject. As a result, a band exhibiting the periodontopathic organism cell surface polypeptide specific to the serum of a patient suffering with a periodontal disease was observed.

By a microorganism containing a recombinant DNA wherein a DNA encoding the periodontopathic organism cell surface polypeptide of Porphyromonas gingivalis of the invention was integrated, the cell surface polypeptide of a periodontopathic organism useful for prophylaxis and diagnosis of periodontal diseases can be obtained in a large amount. Therefore, the invention can be utilized in diagnostic medicament, prophylactic vaccine, etc. of periodontal diseases.

    __________________________________________________________________________     #             SEQUENCE LISTING                                                 - (1) GENERAL INFORMATION:                                                     -    (iii) NUMBER OF SEQUENCES:  3                                             - (2) INFORMATION FOR SEQ ID NO:1:                                             -      (i) SEQUENCE CHARACTERISTICS:                                                     (A) LENGTH:  563 ami - #no acid                                                (B) TYPE:  amino aci - #d                                                      (C) STRANDEDNESS:  sing - #le                                                  (D) TOPOLOGY:  linear                                                -     (ii) MOLECULE TYPE:                                                      -     (vi) ORIGINAL SOURCE:                                                              (A) ORGANISM:  Porphyro - #monas (Bacteroides) gingivalis                      (B) STRAIN:  OMZ409                                                  -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:1:                                  - Met Lys Leu Asn Lys Met Phe Leu Val Gly Al - #a Leu Leu Ser Leu Gly          #                 10                                                           - Phe Ala Ser Cys Ser Lys Glu Gly Asn Gly Pr - #o Asp Pro Asp Asn Ala          #             25                                                               - Ala Lys Ser Tyr Met Ser Met Thr Leu Ser Me - #t Pro Met Gly Ser Ala          #         40                                                                   - Arg Ala Gly Asp Gly Gln Asp Gln Ala Asn Pr - #o Asp Tyr His Tyr Val          #     55                                                                       - Gly Glu Trp Ala Gly Lys Asp Lys Ile Glu Ly - #s Val Ser Ile Tyr Met          # 75                                                                           - Val Pro Gln Gly Gly Pro Gly Leu Val Glu Se - #r Ala Glu Asp Leu Asp          #                 90                                                           - Phe Gly Thr Tyr Tyr Glu Asn Pro Thr Ile As - #p Pro Ala Thr His Asn          #            105                                                               - Ala Ile Leu Lys Pro Lys Lys Gly Ile Lys Va - #l Asn Ser Ala Val Gly          #       120                                                                    - Lys Thr Val Lys Val Tyr Val Val Leu Asn As - #p Ile Ala Gly Lys Ala          #   135                                                                        - Lys Ala Leu Leu Ala Asn Val Asn Ala Ala As - #p Phe Asp Ala Lys Phe          140                 1 - #45                 1 - #50                 1 -        #55                                                                            - Lys Glu Val Ile Glu Leu Ser Thr Gln Ala Gl - #n Ala Leu Gly Thr Val          #               170                                                            - Ala Asp Gly Pro Asn Pro Ala Thr Ala Ala Gl - #y Lys Ile Ala Lys Lys          #           185                                                                - Asn Gly Thr Thr Asp Glu Thr Ile Met Met Th - #r Cys Leu Gln Pro Ser          #       200                                                                    - Asp Ala Leu Thr Ile Glu Ala Ala Val Ser Gl - #u Ala Asn Ala Ile Ala          #   215                                                                        - Gly Ile Lys Asn Gln Ala Lys Val Thr Val Gl - #u Arg Ser Val Ala Arg          220                 2 - #25                 2 - #30                 2 -        #35                                                                            - Ala Met Val Ser Thr Lys Ala Gln Ser Tyr Gl - #u Ile Lys Ala Thr Thr          #               250                                                            - Gln Ile Gly Glu Ile Ala Ala Gly Ser Val Le - #u Ala Thr Ile Thr Asp          #           265                                                                - Ile Arg Trp Val Val Ala Gln Gly Glu Arg Ar - #g Gln Tyr Leu Ser Lys          #       280                                                                    - Lys Arg Gly Thr Val Pro Glu Asn Thr Trp Va - #l Thr Pro Gly Ser Gly          #   295                                                                        - Phe Val Pro Thr Ser Ser Thr Phe His Thr As - #n Ala Thr Glu Tyr Tyr          300                 3 - #05                 3 - #10                 3 -        #15                                                                            - Asp Tyr Ala Gly Leu Trp Glu Asp His Asn Th - #r Asn Glu Ala Val Ile          #               330                                                            - Ser Gly Thr Gln Val Pro Thr Leu Ala Asp Ty - #r Gln Leu Gln Asp Val          #           345                                                                - Thr Gly Glu Leu Ala Asn Ala Leu Ser Gly Ly - #s Phe Leu Leu Pro Asn          #       360                                                                    - Thr His Lys Ser Gly Ala Asn Ala Ala Ser Se - #r Asp Tyr Lys Arg Gly          #   375                                                                        - Asn Thr Ala Tyr Val Leu Val Arg Ala Lys Ph - #e Thr Pro Lys Lys Glu          380                 3 - #85                 3 - #90                 3 -        #95                                                                            - Ala Phe Ile Asp Arg Gly Lys Thr Tyr Ser As - #p Asn Thr Ala Val Pro          #               410                                                            - Glu Tyr Val Ala Gly Glu Asp Phe Phe Val Gl - #y Glu Asn Gly Gln Phe          #           425                                                                - Tyr Val Ser Met Lys Ser Val Thr Asp Pro Ly - #s Val Gly Gly Val Ala          #       440                                                                    - Gly Met Lys Ala His Lys Tyr Val Lys Gly Ly - #s Val Leu Tyr Tyr Ala          #   455                                                                        - Trp Leu Asn Pro Ser Thr Thr Ser Pro Asp Se - #r Trp Trp Asn Ser Pro          460                 4 - #65                 4 - #70                 4 -        #75                                                                            - Val Val Arg Asn Asn Ile Tyr His Ile His Il - #e Lys Ser Ile Lys Lys          #               490                                                            - Leu Gly Phe Asn Trp Asn Pro Leu Val Pro As - #p Pro Asp Pro Ser Asn          #           505                                                                - Pro Glu Asn Pro Asn Asn Pro Asp Pro Asn Pr - #o Asp Glu Pro Gly Thr          #       520                                                                    - Pro Val Pro Thr Asp Pro Glu Gln Pro Leu Pr - #o Asp Gln Asp Thr Phe          #   535                                                                        - Met Ser Val Glu Val Thr Val Leu Pro Trp Ly - #s Val His Ser Tyr Glu          540                 5 - #45                 5 - #50                 5 -        #55                                                                            - Val Asp Leu                                                                          558                                                                    - (2) INFORMATION FOR SEQ ID NO:2:                                             -      (i) SEQUENCE CHARACTERISTICS:                                                     (A) LENGTH:  20 base - #s                                                      (B) TYPE:  nucleic a - #cid                                                    (C) STRANDEDNESS:  sing - #le                                                  (D) TOPOLOGY:  linear                                                -     (ii) MOLECULE TYPE:  DNA                                                 -     (ix) FEATURE:                                                                      (A) NAME/KEY:  CDS                                                             (B) LOCATION:  1..20                                                           (C) IDENTIFICATION METHOD: - #  E                                              (D) OTHER INFORMATION:                                               -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:2:                                  # 20               CNGA                                                        - (2) INFORMATION FOR SEQ ID NO:3:                                             -      (i) SEQUENCE CHARACTERISTICS:                                                     (A) LENGTH:  1782 ba - #se pairs                                               (B) TYPE:  nucleic a - #cid                                                    (C) STRANDEDNESS:  doub - #le                                                  (D) TOPOLOGY:  linear                                                -     (ii) MOLECULE TYPE: Genomic DNA                                          -     (vi) ORIGINAL SOURCE:                                                              (A) ORGANISM:  Porphyro - #monas (Bacteroides) gingivalis                      (B) STRAIN:  OMZ409                                                  -     (ix) FEATURE:                                                            35 s - #ignal NAME/KEY:                                                                  (B) LOCATION:  9..14                                                           (C) IDENTIFICATION METHOD: - #  S                                              (D) OTHER INFORMATION:                                               -     (ix) FEATURE:                                                            10 s - #ignal NAME/KEY:                                                                  (B) LOCATION:  32..37                                                          (C) IDENTIFICATION METHOD: - #  S                                              (D) OTHER INFORMATION:                                               -     (ix) FEATURE:                                                                      (A) NAME/KEY:  CDS                                                             (B) LOCATION:  60..1752                                                        (C) IDENTIFICATION METHOD: - #  S                                              (D) OTHER INFORMATION:                                               -     (ix) FEATURE:                                                                      (A) NAME/KEY:  Sig p - #eptide                                                 (B) LOCATION:  60..105                                                         (C) IDENTIFICATION METHOD: - #  S                                              (D) OTHER INFORMATION:                                               -     (ix) FEATURE:                                                                      (A) NAME/KEY:  mat p - #eptide                                                 (B) LOCATION:  208..175 - #2                                                   (C) IDENTIFICATION METHOD: - #  E                                              (D) OTHER INFORMATION:                                               -     (xi) SEQUENCE DESCRIPTION: SEQ ID NO:3:                                  - AGTCTTTCTT TCGACGTTTT TAGAATCAAT TTAATATTAA TCCTTTTAAA CA - #TTTGGCTT          60                                                                           - ATG AAG TTA AAC AAA ATG TTT TTG GTC GGA GC - #A TTG CTC TCA TTG GGC           108                                                                           - TTT GCT TCT TGT AGT AAA GAG GGC AAT GGC CC - #C GAT CCG GAC AAT GCG           156                                                                           - GCG AAG TCG TAT ATG TCT ATG ACG TTG TCC AT - #G CCT ATG GGA AGT GCT           204                                                                           - CGT GCG GGT GAC GGA CAG GAT CAA GCT AAC CC - #T GAT TAC CAT TAT GTA           252                                                                           - GGA GAG TGG GCA GGA AAA GAC AAA ATT GAG AA - #A GTG AGC ATC TAC ATG           300                                                                           - GTG CCT CAG GGT GGC CCT GGG CTT GTG GAG AG - #T GCT GAA GAT CTT GAT           348                                                                           - TTT GGC ACT TAT TAT GAA AAT CCT ACT ATA GA - #T CCT GCA ACC CAC AAT           396                                                                           - GCC ATT TTG AAA CCG AAA AAA GGT ATC AAG GT - #T AAT TCT GCT GTC GGC           444                                                                           - AAG ACG GTT AAA GTA TAT GTG GTG CTC AAT GA - #C ATC GCC GGC AAG GCA           492                                                                           - AAA GCC CTT TTG GCA AAT GTT AAT GCA GCA GA - #C TTT GAT GCT AAA TTC           540                                                                           - AAA GAG GTA ATC GAA CTG TCT ACT CAG GCT CA - #G GCT TTA GGT ACG GTA           588                                                                           - GCC GAT GGC CCG AAT CCT GCT ACA GCG GCT GG - #A AAG ATT GCC AAA AAG           636                                                                           - AAT GGT ACT ACT GAT GAG ACA ATC ATG ATG AC - #C TGT TTG CAG CCT TCT           684                                                                           - GAT GCT TTG ACT ATC GAA GCT GCT GTA TCC GA - #G GCC AAT GCT ATC GCA           732                                                                           - GGG ATT AAG AAT CAG GCC AAG GTT ACG GTG GA - #G CGT TCT GTA GCA CGT           780                                                                           - GCG ATG GTT TCA ACG AAA GCC CAG AGT TAT GA - #A ATT AAA GCC ACT ACT           828                                                                           - CAA ATT GGA GAA ATT GCC GCA GGT TCT GTT TT - #G GCT ACC ATT ACG GAT           876                                                                           - ATC AGA TGG GTT GTT GCT CAA GGA GAA CGT CG - #C CAA TAC CTA AGC AAG           924                                                                           - AAA AGA GGA ACT GTT CCA GAA AAT ACT TGG GT - #T ACT CCG GGT TCT GGT           972                                                                           - TTC GTT CCT ACC AGC AGC ACT TTC CAT ACA AA - #T GCT ACT GAG TAT TAT          1020                                                                           - GAT TAT GCT GGT CTG TGG GAA GAT CAT AAT AC - #A AAT GAG GCC GTA ATC          1068                                                                           - AGT GGA ACT CAA GTG CCG ACT TTG GCT GAT TA - #T CAG CTC CAG GAC GTG          1116                                                                           - ACT GGC GAA TTG GCA AAT GCT CTT TCA GGG AA - #A TTC CTG CTG CCT AAT          1164                                                                           - ACC CAT AAG TCA GGA GCT AAT GCT GCC TCG TC - #A GAC TAT AAG AGA GGT          1212                                                                           - AAT ACT GCC TAT GTA TTA GTT CGT GCG AAG TT - #T ACT CCC AAG AAA GAA          1260                                                                           - GCC TTT ATC GAT AGA GGT AAA ACT TAT TCA GA - #T AAT ACT GCA GTT CCT          1308                                                                           - GAA TAT GTA GCA GGT GAA GAT TTC TTC GTT GG - #T GAG AAT GGC CAG TTC          1356                                                                           - TAT GTG TCT ATG AAA TCC GTT ACA GAC CCC AA - #G GTA GGT GGT GTA GCT          1404                                                                           - GGT ATG AAG GCA CAC AAA TAT GTG AAA GGC AA - #A GTA CTG TAC TAT GCT          1452                                                                           - TGG TTG AAT CCC AGT ACT ACT TCT CCC GAT TC - #A TGG TGG AAT TCC CCT          1500                                                                           - GTT GTG CGC AAC AAT ATC TAC CAT ATC CAC AT - #C AAG AGC ATC AAG AAG          1548                                                                           - TTG GGC TTC AAC TGG AAT CCT TTG GTG CCG GA - #T CCG GAT CCT AGC AAC          1596                                                                           - CCG GAA AAT CCG AAT AAC CCT GAC CCG AAT CC - #G GAT GAG CCG GGT ACT          1644                                                                           - CCC GTT CCT ACA GAT CCC GAG CAA CCC CTA CC - #T GAT CAG GAT ACG TTC          1692                                                                           - ATG TCG GTT GAG GTT ACA GTT TTG CCT TGG AA - #A GTT CAT TCC TAT GAG          1740                                                                           #1782              TAGCTATTG TAAAATTTTC TTTTTGAGGG                             __________________________________________________________________________ 

We claim:
 1. An isolated DNA encoding a cell surface polypeptide of Porphyromonas gingivalis comprising the amino acid sequence shown in SEQ ID NO:
 1. 2. The isolated DNA according to claim 1, comprising the nucleic acid sequence shown in SEQ ID NO:
 3. 3. A recombinant DNA comprising the DNA according to claim
 1. 4. The recombinant DNA according to claim 3, wherein the recombinant DNA is plasmid pCSP409.
 5. A microorganism containing a recombinant DNA comprising a DNA encoding a cell surface polypeptide of Porphyromonas gingivalis comprising the amino acid sequence shown in SEQ ID NO:
 1. 6. The microorganism according to claim 5, wherein the DNA comprises the nucleic acid sequence shown in SEQ ID NO:
 3. 7. The microorganism according to claim 5, wherein the microorganism is Escherichia coli.
 8. The microorganism according to claim 7, which is Escherichia coli CSP409 deposited under accession number FERM BP-467.
 9. A purified cell surface polypeptide of Porphyromonas gingivalis comprising the amino acid sequence shown in SEQ ID NO:
 1. 10. The purified cell surface polypeptide according to claim 9, which is encoded by the nucleic acid sequence shown in SEQ ID NO:
 3. 11. A method for producing a cell surface polypeptide of Porphyromonas gingivalis, which comprises culturing a microorganism containing a recombinant DNA comprising a DNA encoding a cell surface polypeptide of Porphyromonas gingivalis having the amino acid sequence shown in SEQ ID NO: 1 under conditions suitable for expressing the cell surface polypeptide.
 12. The method according to claim 11, wherein the recombinant DNA comprises the nucleic acid sequence shown in SEQ ID NO:
 3. 13. The method according to claim 11, wherein the recombinant DNA is plasmid pCSP409.
 14. The method according to claim 11, wherein the microorganism is Escherichia coli.
 15. The method according to claim 11, wherein the microorganism is Escherichia coli CSP409. 